Optical storage medium

Abstract

In an optical storage medium, preferably a CD or DVD, comprising a spiral track which consists of pits following one another, a hologram is superimposed in the recording region. To achieve a great security against faking by the superimposition with the hologram, without the good recognisability of the hologram being substantially impaired on its reconstruction, the hologram is introduced at least into one information carrier, for example into the surface region of the recording region including the pit.

1 . An optical storage medium, preferably a CD or DVD, comprising a spiral track which consists of pits following one another and on which a hologram is superimposed in the recording region,  
       characterized in that 
 at least one hologram is introduced into one surface region of the recording region including the information carriers, e.g. into the surface region including the pits.  
 
     
     
         2 . A storage medium in accordance with  claim 1 , wherein the ratio of the depths of the holographic phase structure to the depths of the pits amounts to 1:5 to 1:10 and preferably to 1:6.  
     
     
         3 . A storage medium in accordance with either of claims  1  or  2 , wherein the hologram contains electronically readably features.